FIG. 1 illustrates a typical scenario that may be encountered when a user visits another country and uses their mobile phone (which is registered in their home country) to make telephone calls (including calls to a voicemail account) or to send messages (such as short messaging service [SMS] or multimedia messaging service [MMS]).
There are three networks (2, 4, 6) shown in FIG. 1 each of which comprises a gateway mobile switching centre (8, 10, 12) (GMSC) and a home location register (14, 16, 18) (HLR). It is noted that the Home Location Register (HLR) is the main database of permanent subscriber information for a mobile network which is maintained by a subscriber's home carrier (or the network operator where the user initiated the call). The HLR contains pertinent user information, including address, account status, and preferences and, in use, interacts with the GMSC, which is a switch used for call control and processing. The GMSC also serves as a point-of-access to the Public Switched Telephone Network (PSTN—the fixed network).
In FIG. 1 user A is connected to a network 2 other than his home operator's network 4. User B is connected to a third network 6 (which may be a network operator in the same country as user A's home operator).
In order to make or receive a call between user A and user B it is necessary for the call to make two separate international transits. Such an arrangement has a number of drawbacks as detailed below.
Firstly, when user A moves to a new country, he is forced to incur international roaming rates which are significantly higher than regular service charges incurred when the user is not roaming. It is noted that simply forwarding calls received at user A's home mobile number to an international phone number (e.g. a mobile phone registered in the country within which user A is roaming) is generally not possible since network operators have barred services like forwarding to an international number.
Secondly, callers in user A's visited country have to call his home country's number and thus get charged for international calls.
Thirdly, even basic services like receiving an incoming call or accessing a voicemail account are charged to user A at significantly higher rates.
In addition to the call charges issues noted above, it is noted that typically a user's mobile phone will lack some of the features provided by the local network provider when the user is roaming.
It is noted that the above issues are not restricted to voice traffic on the network and it is noted that an SMS (text message) cannot be delivered across multiple SIM cards/mobile numbers held by a subscriber, as there is no forwarding option for the same.
It is also noted that there is no regulatory body that governs international roaming charges which means that roaming users are often in receipt of large phone bills following a period of use outside of their home network.
There have been a number of attempts to address the above issues and these are discussed below. It is noted that there are limitations or restrictions to each of these “solutions” meaning that there has been a failure to provide a comprehensive resolution to the issues described above. None of the proposed solutions below has attracted a mass/general adoption.
One mechanism for addressing the above issues is for a user to hold multiple SIM cards, one for each country and set forwarding on all other numbers to the voicemail when he is not reachable. This solution however has a number of disadvantages. Firstly, this solution represents a completely manual task for the user, wherein there is a huge scope for the user unknowingly making mistakes such as not setting the forwarding on one of the numbers to voicemail thus effectively dropping all the calls to that number. In addition the user is required to manually switch between SIM cards whenever the user moves between different countries. Secondly, in the multiple SIM card arrangement, the user is billed by all the individual operators of the SIM cards separately, thus making it difficult to manage the bills. Thirdly, a user who has moved to a new country cannot receive calls from the previous country's number unless the network operator allows the setting up of a call forwarding function to an international number at international calling costs (which is rarely possible). Finally, services like voicemail access are tightly coupled to the local identity of the user. There is no way of receiving voicemail drop intimation when the corresponding number is unreachable or inactive. Also, the user has to manually access the voicemail box of all individual numbers by calling internationally and paying international roaming charges.
An alternative mechanism for addressing the above issues is a callback based solution: where a user calls up a number and submits the number he wishes to call. The system then first makes an incoming call to the user and then places the call to the number the user has submitted. It is noted that this mechanism solves the outgoing call problem. However, the user still has to subscribe for international roaming to receive incoming calls, and those charges are significantly higher than home network call charges. It is also noted that this is an unusual way of making a call and is a complete change in the user experience of the way phone calls are made. Other drawbacks of this service are that it doesn't actually save much in call charges except for some reduction in outgoing calls costs. A significant disadvantage is that this way of making a call suffers from extremely high post-dial delays.
A further alternative mechanism comprises the use of a voice over internet protocol (VoIP) solution where the SIM intercepts the outgoing call and routes the call onto internet using VoIP network. Although call rates of IP are cheaper this solution doesn't drastically reduce the cost as the calls to the VoIP gateway are still charged at international roaming rates. Further this mechanism suffers from the fact that all incoming calls reach the user at international roaming costs.
All the above solutions also suffer from the problem of lack of consolidation of services like voicemail, forwarding function and billing. In one way or the other, all the above-described solutions change the user-feel (user-experience) of the way phone calls are made. Post-dial delays are without doubt also significantly high.
Mobile users roaming in multiple countries, especially, frequent travelers having business across different countries, are amongst the worst hit. Consider the following example for a user who frequently travels between India, U.K and U.S. The user would have a SIM from India and thus would have to subscribe to that operator's ‘International roaming’ service to make or receive calls to that number, while out of the home country. The associated costs of usage of the mobile phone when the user is on the move are significantly high, given the fact that every operator on which the user is roaming would impose additional charges per service used (SMS/Call/GPRS) which, if the number had been local, would not have been applicable at all. Moreover, the user is even charged for all incoming calls which otherwise if he uses a local phone is either absolutely free or relatively cheap. These factors inhibit the usage of the mobile phone due to uncertainty in the pricing policy adopted by different operators. Additionally, there is no international body which can regulate an operator's transit charges for calls originated when the user is on ‘international roaming’.
It is also noted that prior efforts to address the issues arising when roaming have not addressed the issue of providing an SMS forwarding solution.
The present invention seeks to overcome or at least substantially reduce the above mentioned problems.